Successful integration of sensor cabling on tool surfaces through additive manufacturing technologies

The SUSIE project consortium has successfully integrated four-wire cabling on the surface of tool steels: “A fundamental step, that will allow the sensoring and capture of data from areas of difficult access of dies and manufacturing tools”.

In some of the material transformation processes many relevant events occur in areas of difficult access where, due to the working conditions, specific data and process parameters cannot be directly captured. As a result, these processes are monitored by means of indirect data; the same problem affects modelling and simulation processes which are fed by these parameters.

To fill this gap, the SUSIE project consortium led by AZTERLAN Metallurgy Research Centre, has achieved a significant advance that will facilitate the sensoring of these critical areas; “we have managed to integrate wiring in the surface of steel tooling by means of additive technology”.

In the words of the project team, “ensuring power supply and signal extraction is a critical first step towards implementing a surface sensor-system in the manufacturing tools”.  The research team has successfully completed the first of the objectives they had set with the subcutaneous insertion of the cabling that will provide tension to the transducer and will transfer the data captured by it.

First experience of success at implementing 4-wire cabling

The cabling system integrated by the working team consists of four sheathed wires protected by mineral insulation. “As far as we know, this is the first experience that has been successfully achieved in this field”; and they add that “there are some previous experiences of thermocouples and cabling embedding. However, we do not know of any case that has been performed by integrating 4-wire cabling in the conditions that we have developed”.

To achieve this milestone, the SUSIE consortium has used the Laser Metal Deposition technology (LMD). “We have been able to perform a controlled welding, with a low heat input, to prevent deteriorating the substrate (tool metal) or the wiring”. In fact, identifying the working thresholds at which a successful welding is achieved without harming these elements is a high value finding.

Surface wiring welding process using LMD

The video accompanying these lines shows the process of subcutaneous insertion of the four-wire cabling in tool steel using additive Laser Metal Deposition technologies:

1. Preheating of the tool metal surface to reduce the aggressiveness of the process. Thin welding beads are made on smooth blocks with a very low heat input to check how they affect the integrity of the substrate. The effect of different metal addition thicknesses and heat levels is compared.
2. The same welding process is performed on tubes (due to its greater similarity with cables) because the curvatures affect the heat diffusion. Several welding beads of reference make it possible to identify the threshold at which the welding is successfully performed, without deteriorating the substrate.
3. Wiring integration: four-wire cabling sheathed and protected by mineral insulation are welded on the surface of the tool steel, ensuring their integrity, and making it possible a successful integration providing power to the sensor, as well as transferring the captured data.

Presentation at MESIC 2021

The results of this research work will be presented at MESIC 2021 (Manufacturing Engineering Society International Conference) which will take place in Gijón (Spain) on June 23rd, 24th and 25th.

The SUSIE project is supported by the ELKARTEK 2020 programme of the Basque Government (file number KK-2020/00063) and has a total budget of 612,000€. It is led by AZTERLAN Metallurgy Research Centre, member of the BRTA, with the participation of TEKNIKER and TECNALIA technology centres and in close collaboration with the MU and UPV/EHU universities, which work on the technical developments of the project and INVEMA (Supply/Demand Intermediate Agent within the Basque Science and Technology Network) which carries out dissemination and industrial contrast activities.